Description : A proponent of a downstream upgrading petroleum plant in Venezuela requested to carry out the mandatory complete EIA report with an Environmental Management System in mind. In Venezuela, a complete EIA report is a document that includes: the Environmental Impact Assessment, the Supervision Plan, the Surveillance Plan, and the Guidelines for a Contingency Plan. For this task, a methodology was proposed to review the role of a complete EIA report within the framework of the requirements of a future Environmental Management System. The outcome was a Proposed Working Model that was applied to the case study. The results showed that the linkage sustains the ongoing use of the complete EIA report in the process of environmental evaluation throughout the life cycle of an industrial plant. In addition, outcomes from the linkage substantially improved the Environmental Supervision Plan in particular.